// Formatting library for C++ - experimental range support
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
//
// Copyright (c) 2018 - present, Remotion (Igor Schulz)
// All Rights Reserved
// {fmt} support for ranges, containers and types tuple interface.

#ifndef FMT_RANGES_H_
#define FMT_RANGES_H_

#include <initializer_list>
#include <type_traits>

#include "format.h"

FMT_BEGIN_NAMESPACE

template <typename Char, typename Enable = void>
struct formatting_range
{
#ifdef FMT_DEPRECATED_BRACED_RANGES
    Char prefix = '{';
    Char postfix = '}';
#else
    Char prefix = '[';
    Char postfix = ']';
#endif

    template <typename ParseContext>
    FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin())
    {
        return ctx.begin();
    }
};

template <typename Char, typename Enable = void>
struct formatting_tuple
{
    Char prefix = '(';
    Char postfix = ')';

    template <typename ParseContext>
    FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin())
    {
        return ctx.begin();
    }
};

namespace detail
{

template <typename RangeT, typename OutputIterator>
OutputIterator copy(const RangeT &range, OutputIterator out)
{
    for (auto it = range.begin(), end = range.end(); it != end; ++it) *out++ = *it;
    return out;
}

template <typename OutputIterator>
OutputIterator copy(const char *str, OutputIterator out)
{
    while (*str) *out++ = *str++;
    return out;
}

template <typename OutputIterator>
OutputIterator copy(char ch, OutputIterator out)
{
    *out++ = ch;
    return out;
}

template <typename OutputIterator>
OutputIterator copy(wchar_t ch, OutputIterator out)
{
    *out++ = ch;
    return out;
}

/// Return true value if T has std::string interface, like std::string_view.
template <typename T>
class is_std_string_like
{
    template <typename U>
    static auto check(U *p) -> decltype((void)p->find('a'), p->length(), (void)p->data(), int());
    template <typename>
    static void check(...);

   public:
    static FMT_CONSTEXPR_DECL const bool value =
        is_string<T>::value || !std::is_void<decltype(check<T>(nullptr))>::value;
};

template <typename Char>
struct is_std_string_like<fmt::basic_string_view<Char>> : std::true_type
{
};

template <typename... Ts>
struct conditional_helper
{
};

template <typename T, typename _ = void>
struct is_range_ : std::false_type
{
};

#if !FMT_MSC_VER || FMT_MSC_VER > 1800

#define FMT_DECLTYPE_RETURN(val)    \
    ->decltype(val) { return val; } \
    static_assert(true, "")  // This makes it so that a semicolon is required after the
                             // macro, which helps clang-format handle the formatting.

// C array overload
template <typename T, std::size_t N>
auto range_begin(const T (&arr)[N]) -> const T *
{
    return arr;
}
template <typename T, std::size_t N>
auto range_end(const T (&arr)[N]) -> const T *
{
    return arr + N;
}

template <typename T, typename Enable = void>
struct has_member_fn_begin_end_t : std::false_type
{
};

template <typename T>
struct has_member_fn_begin_end_t<
    T, void_t<decltype(std::declval<T>().begin()), decltype(std::declval<T>().end())>>
    : std::true_type
{
};

// Member function overload
template <typename T>
auto range_begin(T &&rng) FMT_DECLTYPE_RETURN(static_cast<T &&>(rng).begin());
template <typename T>
auto range_end(T &&rng) FMT_DECLTYPE_RETURN(static_cast<T &&>(rng).end());

// ADL overload. Only participates in overload resolution if member functions
// are not found.
template <typename T>
auto range_begin(T &&rng)
    -> enable_if_t<!has_member_fn_begin_end_t<T &&>::value, decltype(begin(static_cast<T &&>(rng)))>
{
    return begin(static_cast<T &&>(rng));
}
template <typename T>
auto range_end(T &&rng)
    -> enable_if_t<!has_member_fn_begin_end_t<T &&>::value, decltype(end(static_cast<T &&>(rng)))>
{
    return end(static_cast<T &&>(rng));
}

template <typename T, typename Enable = void>
struct has_const_begin_end : std::false_type
{
};
template <typename T, typename Enable = void>
struct has_mutable_begin_end : std::false_type
{
};

template <typename T>
struct has_const_begin_end<
    T, void_t<decltype(detail::range_begin(std::declval<const remove_cvref_t<T> &>())),
              decltype(detail::range_begin(std::declval<const remove_cvref_t<T> &>()))>>
    : std::true_type
{
};

template <typename T>
struct has_mutable_begin_end<T, void_t<decltype(detail::range_begin(std::declval<T>())),
                                       decltype(detail::range_begin(std::declval<T>())),
                                       enable_if_t<std::is_copy_constructible<T>::value>>>
    : std::true_type
{
};

template <typename T>
struct is_range_<T, void> : std::integral_constant<bool, (has_const_begin_end<T>::value ||
                                                          has_mutable_begin_end<T>::value)>
{
};

template <typename T, typename Enable = void>
struct range_to_view;
template <typename T>
struct range_to_view<T, enable_if_t<has_const_begin_end<T>::value>>
{
    struct view_t
    {
        const T *m_range_ptr;

        auto begin() const FMT_DECLTYPE_RETURN(detail::range_begin(*m_range_ptr));
        auto end() const FMT_DECLTYPE_RETURN(detail::range_end(*m_range_ptr));
    };
    static auto view(const T &range) -> view_t { return {&range}; }
};

template <typename T>
struct range_to_view<T,
                     enable_if_t<!has_const_begin_end<T>::value && has_mutable_begin_end<T>::value>>
{
    struct view_t
    {
        T m_range_copy;

        auto begin() FMT_DECLTYPE_RETURN(detail::range_begin(m_range_copy));
        auto end() FMT_DECLTYPE_RETURN(detail::range_end(m_range_copy));
    };
    static auto view(const T &range) -> view_t { return {range}; }
};
#undef FMT_DECLTYPE_RETURN
#endif

/// tuple_size and tuple_element check.
template <typename T>
class is_tuple_like_
{
    template <typename U>
    static auto check(U *p) -> decltype(std::tuple_size<U>::value, int());
    template <typename>
    static void check(...);

   public:
    static FMT_CONSTEXPR_DECL const bool value = !std::is_void<decltype(check<T>(nullptr))>::value;
};

// Check for integer_sequence
#if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
template <typename T, T... N>
using integer_sequence = std::integer_sequence<T, N...>;
template <size_t... N>
using index_sequence = std::index_sequence<N...>;
template <size_t N>
using make_index_sequence = std::make_index_sequence<N>;
#else
template <typename T, T... N>
struct integer_sequence
{
    using value_type = T;

    static FMT_CONSTEXPR size_t size() { return sizeof...(N); }
};

template <size_t... N>
using index_sequence = integer_sequence<size_t, N...>;

template <typename T, size_t N, T... Ns>
struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...>
{
};
template <typename T, T... Ns>
struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...>
{
};

template <size_t N>
using make_index_sequence = make_integer_sequence<size_t, N>;
#endif

template <class Tuple, class F, size_t... Is>
void for_each(index_sequence<Is...>, Tuple &&tup, F &&f) FMT_NOEXCEPT
{
    using std::get;
    // using free function get<I>(T) now.
    const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
    (void)_;  // blocks warnings
}

template <class T>
FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> get_indexes(T const &)
{
    return {};
}

template <class Tuple, class F>
void for_each(Tuple &&tup, F &&f)
{
    const auto indexes = get_indexes(tup);
    for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
}

template <typename Range>
using value_type = remove_cvref_t<decltype(*detail::range_begin(std::declval<Range>()))>;

template <typename OutputIt>
OutputIt write_delimiter(OutputIt out)
{
    *out++ = ',';
    *out++ = ' ';
    return out;
}

template <typename Char, typename OutputIt, typename Arg,
          FMT_ENABLE_IF(is_std_string_like<typename std::decay<Arg>::type>::value)>
OutputIt write_range_entry(OutputIt out, const Arg &v)
{
    *out++ = '"';
    out = write<Char>(out, v);
    *out++ = '"';
    return out;
}

template <typename Char, typename OutputIt, typename Arg,
          FMT_ENABLE_IF(std::is_same<Arg, Char>::value)>
OutputIt write_range_entry(OutputIt out, const Arg v)
{
    *out++ = '\'';
    *out++ = v;
    *out++ = '\'';
    return out;
}

template <typename Char, typename OutputIt, typename Arg,
          FMT_ENABLE_IF(!is_std_string_like<typename std::decay<Arg>::type>::value &&
                        !std::is_same<Arg, Char>::value)>
OutputIt write_range_entry(OutputIt out, const Arg &v)
{
    return write<Char>(out, v);
}

}  // namespace detail

template <typename T>
struct is_tuple_like
{
    static FMT_CONSTEXPR_DECL const bool value =
        detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
};

template <typename TupleT, typename Char>
struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>>
{
   private:
    // C++11 generic lambda for format()
    template <typename FormatContext>
    struct format_each
    {
        template <typename T>
        void operator()(const T &v)
        {
            if (i > 0) out = detail::write_delimiter(out);
            out = detail::write_range_entry<Char>(out, v);
            ++i;
        }
        formatting_tuple<Char> &formatting;
        size_t &i;
        typename std::add_lvalue_reference<decltype(std::declval<FormatContext>().out())>::type out;
    };

   public:
    formatting_tuple<Char> formatting;

    template <typename ParseContext>
    FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin())
    {
        return formatting.parse(ctx);
    }

    template <typename FormatContext = format_context>
    auto format(const TupleT &values, FormatContext &ctx) -> decltype(ctx.out())
    {
        auto out = ctx.out();
        size_t i = 0;

        detail::copy(formatting.prefix, out);
        detail::for_each(values, format_each<FormatContext>{formatting, i, out});
        detail::copy(formatting.postfix, out);

        return ctx.out();
    }
};

template <typename T, typename Char>
struct is_range
{
    static FMT_CONSTEXPR_DECL const bool value =
        detail::is_range_<T>::value && !detail::is_std_string_like<T>::value &&
        !std::is_convertible<T, std::basic_string<Char>>::value &&
        !std::is_constructible<detail::std_string_view<Char>, T>::value;
};

template <typename T, typename Char>
struct formatter<T, Char,
                 enable_if_t<fmt::is_range<T, Char>::value
// Workaround a bug in MSVC 2017 and earlier.
#if !FMT_MSC_VER || FMT_MSC_VER >= 1927
                             && (has_formatter<detail::value_type<T>, format_context>::value ||
                                 detail::has_fallback_formatter<detail::value_type<T>, Char>::value)
#endif
                             >>
{
    formatting_range<Char> formatting;

    template <typename ParseContext>
    FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin())
    {
        return formatting.parse(ctx);
    }

    template <typename FormatContext>
    typename FormatContext::iterator format(const T &values, FormatContext &ctx)
    {
        auto out = detail::copy(formatting.prefix, ctx.out());
        size_t i = 0;
        auto view = detail::range_to_view<T>::view(values);
        auto it = view.begin();
        auto end = view.end();
        for (; it != end; ++it)
        {
            if (i > 0) out = detail::write_delimiter(out);
            out = detail::write_range_entry<Char>(out, *it);
            ++i;
        }
        return detail::copy(formatting.postfix, out);
    }
};

template <typename Char, typename... T>
struct tuple_join_view : detail::view
{
    const std::tuple<T...> &tuple;
    basic_string_view<Char> sep;

    tuple_join_view(const std::tuple<T...> &t, basic_string_view<Char> s) : tuple(t), sep{s} {}
};

template <typename Char, typename... T>
using tuple_arg_join = tuple_join_view<Char, T...>;

template <typename Char, typename... T>
struct formatter<tuple_join_view<Char, T...>, Char>
{
    template <typename ParseContext>
    FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin())
    {
        return ctx.begin();
    }

    template <typename FormatContext>
    auto format(const tuple_join_view<Char, T...> &value, FormatContext &ctx) ->
        typename FormatContext::iterator
    {
        return format(value, ctx, detail::make_index_sequence<sizeof...(T)>{});
    }

   private:
    template <typename FormatContext, size_t... N>
    auto format(const tuple_join_view<Char, T...> &value, FormatContext &ctx,
                detail::index_sequence<N...>) -> typename FormatContext::iterator
    {
        using std::get;
        return format_args(value, ctx, get<N>(value.tuple)...);
    }

    template <typename FormatContext>
    auto format_args(const tuple_join_view<Char, T...> &, FormatContext &ctx) ->
        typename FormatContext::iterator
    {
        // NOTE: for compilers that support C++17, this empty function instantiation
        // can be replaced with a constexpr branch in the variadic overload.
        return ctx.out();
    }

    template <typename FormatContext, typename Arg, typename... Args>
    auto format_args(const tuple_join_view<Char, T...> &value, FormatContext &ctx, const Arg &arg,
                     const Args &...args) -> typename FormatContext::iterator
    {
        using base = formatter<typename std::decay<Arg>::type, Char>;
        auto out = base().format(arg, ctx);
        if (sizeof...(Args) > 0)
        {
            out = std::copy(value.sep.begin(), value.sep.end(), out);
            ctx.advance_to(out);
            return format_args(value, ctx, args...);
        }
        return out;
    }
};

FMT_MODULE_EXPORT_BEGIN

/**
  \rst
  Returns an object that formats `tuple` with elements separated by `sep`.

  **Example**::

    std::tuple<int, char> t = {1, 'a'};
    fmt::print("{}", fmt::join(t, ", "));
    // Output: "1, a"
  \endrst
 */
template <typename... T>
FMT_CONSTEXPR auto join(const std::tuple<T...> &tuple, string_view sep)
    -> tuple_join_view<char, T...>
{
    return {tuple, sep};
}

template <typename... T>
FMT_CONSTEXPR auto join(const std::tuple<T...> &tuple, basic_string_view<wchar_t> sep)
    -> tuple_join_view<wchar_t, T...>
{
    return {tuple, sep};
}

/**
  \rst
  Returns an object that formats `initializer_list` with elements separated by
  `sep`.

  **Example**::

    fmt::print("{}", fmt::join({1, 2, 3}, ", "));
    // Output: "1, 2, 3"
  \endrst
 */
template <typename T>
auto join(std::initializer_list<T> list, string_view sep) -> join_view<const T *, const T *>
{
    return join(std::begin(list), std::end(list), sep);
}

FMT_MODULE_EXPORT_END
FMT_END_NAMESPACE

#endif  // FMT_RANGES_H_
